When glycofurol was administered in multiple doses, it markedly decreased the pharmacological effects of hexobarbital and zoxazolamine, through induction of cytochrome P-450 (Biochem. Pharm. 27:2851,1978). The induction somewhat resembled the induction by phenobarbital and 3-methylcholanthrene of detoxication pathways of xenobiotics. However, a unique property of glycofurol induction was the decreased formation of reactive metabolites of carbon tetrachloride. Therefore, SDS polyacrylamide gel electrophoresis has been used to determine whether a novel form of cytochrome P-450 is induced by glycofurol.